Should the secret message of Shamir's secret-sharing algorithm be interpreted and processed byte by byte? Interpreting it byte by byte makes it easier to process, but in case one of the shareholders decides to tamper with some of the bytes in his possession, this will affect the secret reconstruction. This is a serious risk, and I don't know how it could be prevented.
Would it be sensible, as an alternative, to interpret the secret message as a whole string, instead of byte by byte, transforming it into an integer? In this case, what I am worried about is the huge size of the integer...